Fuse plug



Sept. 11, 1934. H A SOWKA 1,973,396

FUSE PLUG Filed Nv. 7. 1932 Inventor ,/1 llomey the block 8 there is provided a centrally located Patented Sept. 1l, 1934 UNITED STATES PATENT OFFICE 2 Claims.

My invention relates to electrical fuse plugs, and particularly to a. fuse plug having a renewable fusible element, and an important object of my invention is to provide a fuse plug of this type of new and novel form and construction,

and which is economical and easy to use.

Other objects and advantages of my invention will be apparent from a reading of the following description in connection with the drawing, wherein for purposes of illustration I have shown a preferred embodiment of the invention.

Figure 1 is a transverse vertical sectional View through a plug embodying my invention.

Figure 2 is a top plan view of Figure 1.

Figure 3 is a top plan View of the stationary plug portion.

Figure 4 is a View similar to Figure 3y showing the fusible element in place.

Referring in detail to the drawing, wherein like vnumerals refer to like parts throughout the same,

the numeral 5 refers generally to the embodiment, which comprises the stationary plug member 6 and the removable cap member 7.

The plug member 6 comprises a dielectric block 8 of suitable form approaching a cylindrical outline. It is provided exteriorly near one end with a suitable metallic threaded member 9 for making electrical contact with the threaded interior of the receptor of an outlet. At the same end of longitudinally and is spaced from the tube 13 as shown in Figure l. The upper ends of the tubes 13, 15 communicate with a transversely elongated recess 16 formed in the end of the block 8 opposite that on which the contact 10 is located.

Adapted to be laid in the recess 16 over and in contact with the upper ends of the tubes 13, 15 is a conformably shaped metallic fusible element 16a which has the reduced intermediate portion 17 adapted to fuse or blow-out. The end portions of the fusible element 16a over the upper ends of the tubes 13, l5 are apertured to permit the passage therethrough and into the tubes 13, l5 of metallic rods 18, 19, respectively, which are anchored in the cap 7. Metallic Washers 2O and 21 are circumposed upon the rods 18, 19 and have i l a position between the adjacent face of the cap '7 and the fusible element 16a. The washers are of a thickness to fill up the space between the fusible element and the adjacent face of the cap which rests against the end of the block 6 as shown in Figure l.

The cap 7 comprises a disk-like body 22 of dielectric material which has the centrally located conical recess 23 which has its small end 24 near and over the intermediate part of the fusible element, so that when it is in position on the plug member 6 the intermediate portion 17 of the fusible member will be exposed to view, so that when the fusible element blows-out the condition will be clearly visible thru the opening 23.

When a fusible element blows-out it is unnecessary to detach the plug member from its receptor. The cap 27 is simply pulled out of the plug member, the fusible element 16a removed from the rods 18, 19 and replaced with a fresh fusible element, and the plug re-inserted in the plug member.

Though I have shown and described herein a preferred embodiment of the invention, it is to be definitely understood that I do not desire to limit the application of the invention thereto, and any change or changes may be made in material and structure and arrangement of parts, Within the spirit of the invention and the scope of the subjoined claims.

What is claimed is:-

1. A fuse plug consisting of a plug member for engaging an outlet socket and a cap member detachably connected to the plug member, said plug member consisting of a dielectric body having a threaded ring Contact and a contact point on one end, a pair of spaced tubular conductors arranged longitudinally in the plug member and having respective connection with the threaded ring contact and the contact point, a fusible plate removably seated in a conforming depression in said remaining end of the plug member and bridging the ends of said tubular conductors eX- posed in said depression; said cap member comprising a dielectric body having a pair of spaced conductor rods slidable into said tubular conductors of said plug member through the exposed ends thereof to place an end of the cap member in abutting relation to the recess-equipped end of the plug member and close the recess therein, and a conductive washer on each of the conductor rods for engaging the upper side of said fusible plate and holding the same in position while said iro cap member is in the said abutting 'relation to the plug member.

2. In a fuse plug, a plug member consisting of a solid dielectric body having a threaded ring contact and a contact point on one end, a pair of spaced tubular conductors arranged longitudinally in said plug member and having respective connection with said ring Contact and said Contact point and opening through the noor of an elongated depression formed in the opposite end of said plug member; a cap member consisting of an annular dielectric body having a pair of conductor rods slidable into said tubular conducts until said cap member abuts the said opposite end of the plug member and overhangs a portion only of said depression, a fuse strip conformably received in said depression and bridging lying across the ends of said tubular conductors, and a washer on each of said conductor rods arranged to take up the space existing between said cap member and the outer side of said fuse strip after said rods have been passed through openings provided in said use strip and While said cap member is abutted with the said opposite end of the plug member.

f HENRY A. SOWKA. 

